Thanks peaker, although it's been spoken about throughout the thread, I should write something in the first post that says use the more stable unity-5.16.0.
And to re-iterate to symlink the PACKAGES file located in the top directory into your /etc/portage/package.keywords/.
In this way you don't end up with a thousand version dependent entries in your /etc/portage/package* files due to the use of '--autounmask'.

The newer Unity-6.8 is a work in progress and is missing keyword masked for that reason.
The window position bugs are from upstream and are fixed in the latest Quantal release, however this requires gnome-3.6 and Gentoo is in the process of still getting these into the 'gnome' overlay, hence the mask.

You will see me often. I will use unity 6 and place feedback here. It's quite OK for me to deal with some bugs.
I have a backup LXDE in case it will blow up.

Unmasking list needs to be updated, but at later stage.

There are couple of ebuilds for clutter-gst versions 1.6.0 and 1.9.92 in overlay. I will try them now.

Excellent!
We need a few pioneers back in the mix to push things forward
It may be a case of two steps forward, one step back, but that's progress!

I've been working towards getting the Quantal packages integrated with Gentoo's path to Gnome-3.6 via the 'gnome' overlay.
As such to use the experimental Quantal packages ( ie. Unity-6.8 ), you will need to do the following:

It was a deliberate decision not to maintain mask states for packages that lie outside of the overlay.
So that's why you've encountered the need to keyword unmask networkmanager, xorg-drivers and pulseaudio.

Yes, >=gcc:4.6 is needed for grail, unity, nux and frame to build but again is a package that lies outside the overlay.
It might work with gcc:4.7 but I haven't tested this yet.

Unity-gentoo overlay contains a small amount of gnome-3.6 packages that haven't made it into 'gnome' overlay yet.
The clutter-gst-1.9.92 and gstreamer-1.0.1:1.0 ebuilds are in there so we can have cheese-3.6 and totem-3.6.
The clutter-gst-1.6.0 ebuild is in there to modify it's depend on <=cogl-1.10.4:1.0 as it doesn't build against the new cogl-1.12.0 that comes in 'gnome' overlay.

Writing from LXDE.
Completed update after adding 'gnome' overlay. Got some critical errors in logs. After logging in only desktop and icons (home, trash) on it are shown, no panels. File manager can be started by clicking on icons and other apps are starting from file manager. Alt+F4 closes windows. No decorations on windows. "Win" key has no effect.
Same with new user.

(process:2412): GLib-WARNING **: In call to g_spawn_sync(), exit status of a child process was requested but SIGCHLD action was set to SIG_IGN and ECHILD was received by waitpid(), so exit status can't be returned. This is a bug in the program calling g_spawn_sync(); either don't request the exit status, or don't set the SIGCHLD action.

Sorry for the late reply, been stuck working these last couple of days

The cheese and totem deps. have been fixed, they should indeed dep. on clutter-gst:2.0 and gstreamer:1.0.

The "CRITICAL: gsm_manager_set_phase: assertion `GSM_IS_MANAGER (manager)' failed" error you see for gnome-session took me days to track down but is due to polkit-gnome-authentication-agent-1 not being executed on login.
I commited the fix for gnome-extra/polkit-gnome-99.0.105 but failed to revision bump it so that it would be upgraded on next emerge update.
I've done the revbump so should upgrade OK now.

After last patch I'm able to start gnome session. This is great to have a choice.
I haven't reported it, sorry, but gnome-shell was broken in my setup after I added unity-gentoo overlay.

Patch has no effect on unity. No panel, no dash, just desktop with icons.

More debug info:
"startx", then in xterm "unity".
It's the only way I found to actually have panel and dock on screen as a _black_ rectangular areas. There is some functionality, as menus are dropping from elements on the panel, and docked applications could be started by blind click.
I haven't found how to:
1. Make panel and dock decorated, or icons on them to be shown.
2. See the dash. When I hit a Win-key small rectangular area (200x100px) at top left corner comes black representing dash.
3. Make panel or dock take place on screen when unity started as session from startx or gdm.

(process:6026): GLib-WARNING **: In call to g_spawn_sync(), exit status of a child process was requested but SIGCHLD action was set to SIG_IGN and ECHILD was received by waitpid(), so exit status can't be returned. This is a bug in the program calling g_spawn_sync(); either don't request the exit status, or don't set the SIGCHLD action.

Line 3 above took my attention. So I've experimented with panel-service a bit.
"startx" then "/usr/lib64/unity/unity-panel-service"
Not sure that it should be run from an ordinary user.
It isn't crashing, it could be run from startx, gnome-shell or unity session. When it runs menus are removed from windows. So it's kind of functional.

Hello guys,
I'm trying thins a few days to merge Unity 5.16.0 on a fresh Gentoo system (10.0/desktop/gnome)
With just unmasking the needed packages it's not possible

First problem is 'dev-libs/libdbusmenu-99.12.10.2'. It will not compile until the packages 'app-text/gnome-doc-utils' and 'dev-libs/json-glib' are merged into the system. You should add the packages as dependencies.

The second problem is 'unity-base/compiz'. It needs <=mesa-8.0.4. unfortunately is mesa–8.0.4 the current stable version in Gentoo. So I've to downgrade to mesa–8.0.3 by blocking mesa-8.0.4, 'app-admin/eselect-opengl-1.2.6' and 'x11-proto/glproto–1.4.16'.

The next problem is 'x11–base/xorg-server-1.13.0–r9999'. This package needs as dependencies at least '>=x11-proto/randrproto-1.4.0' and '>=x11-proto/glproto-1.4.16'. Otherwise it's not possible, to build i.e. 'xf86-video-intel' or 'xf86-input-wacom' against the server.
You should update the dependencies accordingly.
Updating 'randrproto' is not a proplem, but 'glproto' is blocked to get 'mesa' downgraded for 'compiz'

I hope you see my dilemma

Last but not least, 'gnome-base/gnome-settings-daemon-99.3.4–r2'. It ignores the 'wacom' use-flag and adds 'xf86-input-wacom' as dependency in any case.

Can someone correct the issues, so it would be possible to install Unity just by unmask the required packages? Expecially the problem with the Mesa downgrade.

At the end a question of interest. Is it really necessary to have rhythmbox as dependency for Unity? I know Rhythmbox can be removed under Ubuntu without breaking Unity. My personal favorite is Banshee, I would be happy to avoid the install of Rythmbox.
It exist already a use-flag 'rhythmbox' maybe it can be used to enable/disable the build of Rhythmbox.

The problem looks to be some breakage with dev-libs/dbus-glib after upgrading dev-libs/glib, so re-emerge dbus-glib and see if that fixes.
If no joy then you can try a more sweeping approach to re-emerging all installed dbus packages with:

Code:

emerge -1a $(qlist -IC dbus)

Also from your logs I see that I was not including the possibility of the user manually running /usr/bin/unity within an xsession and so have made some fixes to allow this to hapen.
Forced /usr/bin/unity to use python2 and fixed the unity_support_test missing symlink.

Good luck in the exams!

@renegart
Welcome and thanks for the report, I'll amend the dependency lists.

The music dash lens that is part of the Unity desktop (unity-base/unity-lens-music) can use either rhythmbox or banshee's music collection database.
Rhythmbox was chosen intially as it also plugs into UbuntuOne music store and as far as I can see, there is no such plugin for banshee.
But I can look at adding banshee collection support for the music lens in the near future (and patches welcome of course).

In meantime I found out that 'x11–base/xorg-server-1.13.0–r9999' need also '>=x11-proto/dri2proto-2.8' as dependency and 'dri2ptoto–2.8' needs at least 'mesa-8.0.4-r1'.

Are you sure about it?

No, I did several times try to update dri2proto and it complained about mesa–8.0.4–r1 has to be unmasked to continue. In meantime I've downgraded to mesa–8.0.3-r1 and the update of dri2proto works too. Seems to be my fault.

next problem which confusing me.
I've updated the unity repository this morning. Now protage complains that 'there are no ebuilds to satisfy "dev-libs/boost:1.49"'. Even when I merge boost-1.49 by hand it doesn't makes portage happy. Any ideas why boost is not found? Can it be that 'boost:1.49' is wrong in 'unity-5.16.0' package and should be 'boost–1.49'? Is that a typo?

=unity-base/compiz-0.9.8.4-r1 violates sandbox restrictions, twice.
Was reported. Looks like one of the reasons is in 'cmake/recompile_gsetting_schemas_in_dir_user_env.cmake'. It not uses {$CMAKE_ROOT} or something similar.

OK a quick summary of commits/fixes etc...
* Gstreamer and it's plugins have been bumped to 1.0.2
* Glib has been bumped to 2.34.1
* Mesa version restriction has been removed for unity and compiz
* boost:1.49 has vaporised from the portage tree, overlay packages test OK when depending on any version of boost so slot/version has been removed
* wacom is optional for gnome-settings-daemon again via 'wacom' USE flag
* libappindicator has been added as a dep. for nm-applet and gnome-settings-daemon
* libdbusmenu's dependencies have been updated to include doc-utils and json-glib

Haven't had a chance to fix those sandbox violations for compiz/unity yet but they should be purely cosmetic at this stage and the packages should still install and work.
Let me know if they are fatal or are causing problems.

=unity-base/unity-lens-video-0.3.12 fails compile stage with =dev-python/python-distutils-extra-2.36 from main portage tree.
With =dev-python/python-distutils-extra-2.35::unity-gentoo it compiles. But 2.36 is being keyword-unmasked by PACKAGES file in overlay.

Due to the main tree restricting the use of python-3 with python-distutils-extra, I've bumped the overlay's version to 2.36 for now and had contact with one of the main tree's maintainers.
python-distutils-extra used to fail with python-3 but after version 2.23 it seems to be OK.